The immediate causes: the situation of the postwar
Stalin seeks to put the USSR immune to another attack by creating a "glaze" territorial and ideological, that is to say a protective space which removes the threat of Soviet borders:
pushing further west borders of the USSR by the annexation of the Baltic countries and parts of Poland, while the German territories to the east of the Oder and Neisse Görlitz areplaced under Polish administration (partition effected during the Potsdam Conference);
by imposing pro-Soviet governments in the countries of Central and Eastern Europe occupied by the Red Army (with the exception of Austria), countries which later became the "people's democracies." The Prague coup in Czechoslovakia - one of the few real pre-war democracies in Eastern Europe - was the most visible expression to the west of this policy, and was seen as the manifestation of the hegemonic will of the USSR.
Even before the end of hostilities with Germany, the Soviet Union established its domination in the territories liberated by the Red Army:
arrested sixteen leaders of the Polish Secret Army, formally invited to Moscow for "political talks", the two main leaders of the Polish resistance dying in prison a few months later.The Polish government in exile in London, abandoned by the West, is denied all privileges gradually, and the Lublin Committee formed by the Soviets took control of the country;
allocation of the province of Czechoslovakia Carpathian Ruthenia to the Ukraine, giving the Soviet Union a common border with Hungary;
installation of the communist parties in power in Bucharest as well as Sofia, and elimination of all other political;
establishment in Vienna, without consulting the West, a Soviet-backed interim government headed approved the Anschluss in 1938;
Finally, Marshal Tito, now based in Belgrade, refused, contrary to what the Kremlin promised to the Allies, leaving King Peter II returned from exile.
Increasingly concerned about the repeated violations of the Atlantic Charter and the Declaration on Liberated Europe at Yalta, Churchill was alarmed in a telegram dated May 12, 1945 at Truman risk to see Soviet forces s' advance to the shores of the Atlantic, and already uses the term "Iron Curtain", which became famous. In March 1946, in a resounding speech, he openly denounced the Soviet grip on Eastern and Central Europe."From Stettin in the Baltic to Trieste in the Adriatic an iron curtain has fallen on the continent. (...) The Communist parties, which were very low in all these Eastern States of Europe, obtained a power far beyond their importance, and look everywhere to exercise totalitarian control. Government officers are installed across the point that with the exception of Czechoslovakia, there is no true democracy. "


A takeoff on the V2 test site in Peenemünde on the Baltic Sea, June 21, 1943. With the advent of the era of the Cold War geopolitics, the recovery of the German technology of ballistic missiles is the top priority of the two superpowers: the Ballistic Research Center Peenemünde and the production site will be reviewed Dora-Nordhausen from every angle by the American and Soviet secret services after the fall of the Third Reich.
In Germany, in their occupation zone, the Soviets led denazification strongly determined to the Potsdam Conference. More than 120,000 people were interned in "special camps" that will exist until 1950. 42 000 detainees have died of deprivation and sévices8. This cleansing policy is consistent with the appointment of communist cadres in key positions in administration, police and justice, and thousands of agents who worked under the Third Reich are "recycled" by the new security services of East Germany or maintained in administration9 and many officials of the former regime used the new government until the 1960s.
Western allies, however, rely more on a "reeducation" (Umerziehung) allemand10 the people, coupled with a policy of leniency of "followers" (Mitläufer) and supporters of the regime. German scientists are well recovered by the Joint Intelligence Objectives Agency (JIOA) to work for the United States (Operation Paperclip), while it is permissible for former officials and military of the Third Reich, if n ' have not been convicted by the courts to exercise their functions again. By the end of the war, the Office of Strategic Services (OSS), the embryo of the Central Intelligence Agency (CIA), says the former Major General of the Wehrmacht Reinhard Gehlen, head of the Abwehr to the front is (Abteilung Fremde Heere Ost), the task of creating an information service covering all the territories once occupied by the Allemagne11. To justify its budget - partly used for exfiltration, in collaboration with the ODESSA, former collaborators or Nazi war criminals - this newly created spy network, the precursor of Bundesnachrichtendienst (BND) and named Gehlen Org by U.S. defense, forwards sometimes made entirely of information and more and more worrying about the power of the Soviet Army and the expansionist strategy of the USSR. In 1947, the United States make it a part of their propaganda, when in fact the Soviet Union has not yet begun to recover from conflict mondial12.
It should be noted however that, even assuming that Stalin had no intention of extending by force the sphere of Soviet domination, the USSR did not vassals under his army occupied the country, thanks to the gradual establishment of "people's democracies" and she undertook several attempts to increase by bullying its sphere of influence in Iran (see Iran-Soviet crisis), Greece and Turkey. In the words of Stalin himself, he knew not to go too far if he felt tense resistance to its ambitions.